Oil burner



M. WALSHIN July 10, I956 OIL BURNER Filed Dec. 27, 1951 JNVENTOR. Murray l7 h/sh'n/ ATTORNEY 2,753,929 OIL BURNER Murray Walshin, New York, N. Y., assignor to Silent- Flame Manufacturing (10., inc, New York, N. Y., a corporation of New York Application December 27, 1951, Serial No. 263,647 1 Claim. (Cl. 15876) The present invention relates to oil burning devices and more particularly to an air guiding or blast tube with improved air controlling means.

With oil burning equipment it is important that every effort be made to obtain the best possible intermixing of oil particles and air. When the oil and air are not properly intermixed, their relative proportions being correct, the highest combustion efficiencies are not obtained, which results in higher operating costs, excessive smoke, etc. Numerous attempts have been made to provide oil burners which give maximum combustion efliciency but they have generally been lacking in some respect or other.

The present invention aims to overcome difiiculties such as those referred to above by providing an oil burner having an improved combination of air guiding tube with means for obtaining optimum intermixture and combustion of air and oil, a portion of the means being readily adjustable to obtain best results for any particular installation.

An object of the present invention is to provide a new and improved oil burner.

Another object of the invention is to provide an improved oil burner adapted to give high combustion efllciencies.

Another object of the invention is to provide an oil burner embodying improved means for controlling air passing through an air guiding tube.

Still another object of the invention is to provide an improved oil burner of relatively simple construction and operation.

A still further object of the invention is to provide improved air control means for an oil burner, that does not substantially interfere with flow of air therethrough.

Other and further objects of the invention will be obvious upon an understanding of the illustrative embodiment about to be described, or will be indicated in the appended claim, and various advantages not referred to herein will occur to one skilled in the art upon employment of the invention in practice.

A preferred embodiment of the invention has been chosen for purposes of illustration and description and is shown in the accompanying drawings, forming a part of the specification, wherein:

Fig. 1 is a perspective view showing a preferred embodiment of the present invention;

Fig. 2 is a vertical sectional view taken along line 2-2 of Fig. 1;

Fig. 3 is a sectional view taken along line 33 of Fig. 2;

Fig. 4 is a sectional view taken along line 4-4 of Fig. 2; and

Fig. 5 is a sectional view showing a modified form of a portion of the present invention.

As shown in Fig. 1 the complete oil burner comprises a stand 2 which supports a housing 3, the housing supporting at one side thereof a motor 4 for rotating an impeller (not shown) which is located inside the housing 3. Air is delivered to the interior of the housing through a suitable inlet, and the quantity of air admitted may be controlled by a shiftable control plate 5. Air passes from the housing 3 into one end of an air guiding tube 8, the air passing through the tube and out its open end. A portion of the tube 8 may project through a furnace wall (not shown) so that air flowing through the tube nited States Patent 0 "ice is delivered to the interior of the furnace. Oil is supplied to a nozzle 10 through oil pipe 11, conduit 12 and oil pump 14. The pump 14 is preferably driven by the motor 4 which turns the air impeller. The foregoing parts are generally known.

The present invention is concerned more particularly with the air guiding tube 8 and the air controlling or guiding means contained within it. These features are best shown in Figs. 2 through 4. The air tube 8 which usually extends horizontally into a furnace, has a conical member 16 secured to one end thereof by a screw 17 for converging and better directing an air stream emerging from the open end of the air guiding tube 8.

Air passing through the guiding tube 8 is subjected to different actions at its inner and outer portions. That is, a stream of air passing through the air guiding tube 8 has its outer portions subjected to the action of vanes carried by an annular member 19 and its central portions subjected to the action of vanes carried by a centrally disposed tubular member 20. Each of these members is spaced a short distance inwardly from the outer end of the air guiding tube 8.

The outer annular member 19 has a plurality of inclined vanes 21 arranged around its inner periphery for causing outer portions of air moving through the tube to be whirled spirally. These vanes 21 project inwardly a uniform distance and cooperate to slidingly support the inner tubular member 20. The annular member 19 may be fixedly retained in position by a set screw 22 which extends through an opening in the air guiding tube 8.

The inner tubular member 20 has a cylindrical and substantially imperforate outer surface for confining an annular ring of air between its outer periphery and the inner periphery of the annular member 19. The inclined vanes 21 extend the full distance between these peripheries and whirl the air passing through this annular space. While the fit between the outer periphery of the tubular member 20 and the innermost edges of the vanes 21 is close, the tubular member 20 is supported sufficiently freely for sliding movement to and fro lengthwise of the air tube 8, so thatthe tubular member 20 may be adjusted lengthwise of the air tube 8, as will be hereinafter brought out.

The tubular member 20 guides and controls air which passes through the central portion of the air tube 8. At its interior this tubular member 20 has a plurality of vanes 25, each with its plane radially disposed. Air passing through the tubular member 20 is so constrained as to pass axially straight through the tubular member 20, without whirling. The vanes 25 preferably have lengths along the longitudinal axis of the air tube 8 equal to at least half the length of the tubular member 20, so as to minimize the possibility of air turbulence within the member 20.

The radial vanes 25 terminate at their inner portions in a bearing 26 for supporting the oil pipe 11, and the latter is fixedly secured with the bearing by a set screw 28. The oil pipe extends rearwardly from the tubular member 20 and thence laterally through a slot in the side wall of the casing 3, the rear end of the pipe 11 being connected in any suitable manner with the oil conduit 12. An adjustable plate and set screw 30 facilitates longitudinal adjustment of the oil pipe 11 along the air tube 8, together with the tubular member 20 which is secured thereto.

Mounted on the oil pipe 11 and fixedly held thereto by a set screw 36 is a bracket for supporting the igniting electrodes 32, their lead wires (not shown), and their insulators 33. The bracket comprises a base part 34 and clamp 35. Exterior surfaces of the base part 34 and the clamp 35 are of such contours as to conform closely to the bearing 26 and insulators 33, to thereby minimize interference with the air stream portion which flows through the guiding tube 8 adjacent its center. The set screw or bolt 36 which retains the insulators in fixed position on the oil pipe 11 is aligned withan air guiding vane to further minimize disturbance of air flowing through the tubular member 25.

Each insulator extends into a separate compartment formed by the radial air guiding vanes 25. As shown in' Figs. 3 and 4 an upper of these vanes is disposed intermediate the two insulators 33 and two lower additional vanes 25 are provided, one at each opposite portion of a respective insulator, thus providing a separate compartment for each insulator. The vanes 25 are spaced about 120 apart and extend about one-half the distance through the tubular member 20 so as to insure air flow straight through the tubular member 20 in the direction of the longitudinal axis of the tube 8.

When the oil burner is in use an air stream flows rapidly through the air guiding tube 8. Outer portions of this air stream are set into spiral motion by the vanes 21 intermediate a wall of the annular member 19 and an outer cylindrical Wall of the tubular member 20; there is thus provided what may be termed a spiralling cylinder of air emerging from the outlet end of the annular member 19. The central portion of air moving through the tube 8 is restrained to axial flow by the vanes 25 at the interior of the tubular member 20. These latter vanes isolate the igniting electrodes and their insulators in separate compartments to minimize the possibility of turbulence which might be created if the electrodes and their insulators were in a single compartment and interfering air currents set up. As the spiralling cylinder of air and the straight-flowing central air stream approach the outer end of the air guiding tube8, the conical member 16 directs the spiralling cylinder inwardly so as to give whirling turbulence to the straight-flowing central air stream, which latter stream picked up oil from the nozzle 10. The straight-flowing air passing over the nozzle 10 tends to carry the particles of oil straight out into the furnace. Combustion does nottake place inside the air tube 8 but beyond its end and beyond the cone 16, in a furnace chamber.

For best results with any particular furnace installation the tubular member 20, oil pipe 11 and electrodes 32 may be simultaneously shifted, as a unit, axially of the air tube 3. The outer periphery of the cylindrical tubular member 29 slides along the inner edges of the inclined air vanes 21-, which remain fixed in position due to the set screw 22; The combination of the open ended annular member 19 and the open ended'tubular member 20, with the outer whirling'air cylinder and the inner air stream portion which passes substantially unrestrainedly through the tubular member 20 give'highly satisfactory intermixture of oil and air and relatively high combustion efiiciencies.

While the above described device gives highly satisfactory results in actual operation itmay be desired, in some instances, to utilize an inner tubular memberwhich does not cause straight flow of air through its interior.v A modified form of tubular member 20a, for such purpose, is shown in Fig. 5. This tubular member has air' guiding vanes 40 inclined 'to the length thereof so as to give a whirling or spiralling motion to air which passes through the member 20a. The'vanes 40 could be in clined in the same direction 'as the vanes 21 of thean nular member 19 shown in Figs. 2-4, or could be inclined in the opposite direction. The form illustrated in Figs.

2-4 is preferred, however, as 'it has'beenfoundto give such good results in actual operation.

It will be seen that the present invention provides a.

new and improved oil burner of relatively simple con struction and operation which is adapted to provide maximum intennixture of'oil and fuel and high combustion efliciencies. The air stream which flows in substantially unobstructed manner straight through the inner tubular member picks up oil particles emerging from an oil supply nozzle. These oil particles are thoroughly intermixed with the air under the influence of the whirling or spiralling cylinder of air created by the inwardly projecting inclined vanes of the outer annular member. The two air stream portions are discharged into a furnace chamber in which combustion takes place. The outer periphery of the inner tubular member is freely slidable along inner edges of the air guiding vanes and has a relatively close fit therewith to insure setting in spiralling motion all air which passes through the annular space between the inner tubular member and the outer annular member. The inner member may be shifted simultaneously with its oil pipe and electrodes lengthwise of the air guiding tube, to thereby give the best setting for the oil pipe nozzle 10 and inner tubular member with respect to the annular member which carries the inclined vanes. The vanes at the interior of the inner tubular member isolate the electrodes and their insulators from each other and hold air passing therethrough to substantially straight axial flow.

As various changes may be made in the form, construction and arrangement of the parts herein without depart ing from the spirit and scope of the invention and without sacrificing any of its advantages, it is to be understood that all matter herein is to be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, 1 claim:

In an oil burner the combination of an inner assembly including a central oil pipe, a relatively short tubular member entirely open at its ends and spaced around said oil pipe and coaxial therewith and electrode igniting means all fixed together, a relatively long outer air-guiding tubehaving its forward portion only spaced around said inner assembly and coaxially therewith to provide an annular intervening space and terminating at its forward end in a conical constriction, an air-spiraling member in the intervening space intermediate said air-guiding tube and said tubular member comprising an annular member having circumferentially spaced around its periphery a plurality of spiraled air-guiding vanes, said inner assembly being supported by and slidable along the inner surface of said air-spiraling member, said airspiraling member having an over-all length substantially less'than thelength of the outer air-guiding tube whereby said air-guiding tube extends rearwardly behind the rear end ofthe tubular member and the air-spiraling member so that air supplied to the rear end of said air-guiding tube will flow substantially straight to said tubular member and air-spiraling member and will then divide into a substantially straight-flowing inner stream through said inner tubular member and a surrounding spirally flowing stream through said air-spiraling member, and said airspiraling member having an over-all length substantially greater than said tubular member whereby the relative position 'of the members may be changed by sliding the tubular member along the air-spiraling member to adjust the interaction of the straight and the spiraling air streams adjacent to the air-guiding tube conical constriction.

References Cited in the file of this patent UNITED STATES PATENTS 1,136,849 Tucker Apr. 20, 1915 1,699,623 Novak Jan. 22, 1929 2,066,806 Smith et al. Ian. 5, 1937 2,078,021 Rodler' Apr. 20, 1937 2,156,121 Macrae Apr. 25, 1939 2,181,527 Vollmer Nov. 28, 1939 2,292,664 Schwartz Aug. 11, 1942 2,497,480 Walshin Feb. 14, 1950 2,553,130 Cadella May 15, 1951 2,603,280 Bernhard July 15, 1952 2,609,869 Murphy et al Sept. 9, 1952 2,649,148 Tappet al. Aug. 18, 1953 

